I think the better question is why didn’t everyone else choose wisely by picking lemm.ee? /s
But for real, it’s just like the Jeep wave. See someone else on your instance in the wild? Say hello to each other and say you’re the best instance! Maybe the wave wasn’t the best comparison, but I have a Jeep so I was contractually forced to say so. I think that’s how it works anyway.
I assume because lemmy.world and lemmy.ml have so many people registered that they’re becoming very sluggish. Smaller instances like lemm.ee (and civilloquy.com!) are much easier to actually use because the servers aren’t dying.
Also Beehaw defederated from Lemmy.world so they can’t see each others communities or all of each others replies on a third party server.
Lemm.ee’s admin seems technically proficient too.